Wrench



F. LAMBERT-- WRENCH.

APPLICATION FILED 0CT.22| 1920.

Patented Aug. 30, 1921.

I'NZ.

UNIT-ED STATES FRANK LAMBERT, OF BROOKLYN, NEW YORK, ASSIGNOR TO THOMSON METER COM- PATENT oFFlcE..

PA'NY, A. CORPORATION 0F NEW JERSEY.

WRENCH.

To all whom may concern:

' Be it known that I, lFRANK LAMBERT, a

citizen of the United States, and a resident of Brooklyn, county -of Kings, an'd State of New York, have invented a new .and Improved Wrench, (Case-5,) of which the following is a full, clear, and exact specification.

My present invention relates to wrenches and its object, broadly stated, is to provide a wrench which is automatically rendered inoperative Awhen the turning power applied to it exceeds a predetermined amount.

The wrench of my invention finds special application in cases where, for certain reasons, it is desirable or necessary that fastening devices (such as bolts, headed screws, nuts and the like) be tightened `to a certain degree. As an illustration I may mention the bolts or screws which secure the casing parts of certain water meters where expansion washers or rings are associated with the bolts to permit a separation `of the casing parts when the water in the meter freezes. A construction of that kind is set forth in m Number 32 ,653, filed October 1, 1919. In such a meter, the fastening bolts should not be turned too tight and should, moreover, be tightened as uniformly as possible. With an ordinary wrench thatwould be difficult,

'if not impossible, to accomplish, for no two 'becomes inoperative with respect to the bolt or other member acted upon when the turning power applied by the wrench exceeds a predetermined amount. In other words, by the use'of my new wrench the proper tightening of a bolt, nut, or other fastening member, is assured. .A

In the preferred form of my invention, as I have actually employed it, the jaws of the wrench automatically separate into an inoperative position with respect to the member acted upon by the wrench, when this member has been tightened the right amount. Another way of carrying out the idea of my invention is to provide a yieldable connection between the two jaws and the handle, whereby the handle gives wayunder the application of excessive turning power.

co-pending application, 'Serial' Specification of Letters Patent. Patented Aug, 30, 1921,

Application led October 22, 1920. Serial No. 418,744.

In the drawings, which illustrate two embodiments of my invention,

Figure 1 is a view in elevation of a preferred form of wrench, certain parts'of which have been broken away and shown in cross-section for the sake of clearness;

Fig. 2 is a transverse section on line 2 2 of Fig. 1;

Fig. 3 illustrates the application of the wrench to the Head of a bolt, or similar fastening member; Fig. 4 shows the separation of the jaws into an inoperative position when excessive turning power is applied to the wrench;

Fig. 5 shows a modified form of wrench, certain of the parts being broken away and shown in cross-section for the sake of clearness; and

Fig. 6 is a transverse cross-section on line 6-6 of Fig. 5.

Referring to the form shown in Figs. 1'

to 4, a suitable handle l carries a rod 2 at the outer end of which is fixed the jaw 3. The handle 1 has a screw-threaded opening 4, into which fits the screw-threaded portion 5 of the rod 2, whereby the two parts are rigidly connected together. Broadly speaking, the parts 1 and 2 may besaid to constitute the handle of the wrench. On the rod 2 is slidably mounted the jaw 6, which is adapted to cooperate with'the fixed jaw 3 to engage the member to be acted upon by the wrench. An adjustable nut 7 is mounted on the screw-threaded portion 5 of the rodv2 at the inner end of the handle 1, and between the nuty 7 and the movable jaw 6 is interposed a coil spring 8.l The tendency of this spring is tourge 'the slidable jaw 6 toward the fixed jaw 3.y Suitable means is provided to limit the movement of the jaw 6 under the'action of the spring 8 toward the xed jaw 3. A simple form of such stop means is shown in the drawings as a sleeve or collar 9, mounted on the rod 2 and interposed between the jaws 3 and 6. To prevent turning of the jaw 6 on the rod 2, there is a key or lug 1() adapted to engage in an axial slot or key-way 11 in the rod 2. For convenience of construction, the lugwlO may be formed integral with the jaw 6, as indicated in Fig. 1, in which case the slot 11 will extend to the end of the rod to permit mountbears the outer end of the spring 19. The- The operation of my new wrench will be apparent from the foregoing description and I may briefly explain 'it as follows: In Fig. 3 the member A is intended to represent diagrammatically any suitable form of fastening device,'such as a bolt, screw, nut, or other member adapted to be turned into fastening position. The wrench is applied to this member A in the usual way. Now, as soon as the member A is sufficiently tightened, the further turning of the wrench will result in the separation of the jaws, as shown in Fig. 4, because the resistance offered by the tightening member A is greater than the action of the spring 8 on the movable jaw 6. When this occurs, the jaw 6 is pushed away from the l jaw 3 against the force of the spring 8 and further turning of the wrench has no effect on the member A. In other words, the jaws 3 and 6 automatically separate into an inoperative position with respect to the bolt or other member acted upon, when the turning power applied to said member by said wrench exceeds a predetermined amount. This amount can be readily calculated beforehand by "employing a spring of known tension or resistance. Furthermore, the turnable nut 7 permits the spring to be adjusted to a nicety.

In the modification shown in Figs. 5 and 6, the jaws 12 and 13 are relatively fixed and are pivoted to the handle 14 by means of. a pin 15. The handle 14 is at its inner end provided with a forked extension 16 into which fits the central extension 17 carriedby the jaws. The extensions 16 and 17 are provided with alined openings through which extends the pivot pin 15. The outer ends of the forked extension 16 provide shoulders 18 against which the jaws rest when the parts are held in normal position by the spring 19. Broadly speaking, the springv 19 constitutes a yieldable connection between the jaws and the handle of the wrench. This yieldable connection may be mechanically applied in different ways. In the drawings, I have shown the spring 19 housed within the opening' 20 of thefjaws. the outer end of the opening' 2O is closed byan adjustable set-screw 21, against which other end of the spring engagesthe shoulder 22 of the handle 14. The spring 19 being under tension, its tendency is to swing the jaws 12 and 13 about the pin 15 (assuming,

the -handle to be a fixed part) until the jaws bear against the stop shoulders 18 of the forked extension 16 of the handle. The adjustable set-screw 21 permits a regulation of the tension of the spring 19.

. Assuming that the wrench shown in Figs. 5 and 6 is applied to a bolt or like member, it will work in the way of an ordinary wrench until the fastening member has been tightened a predetermined amount. When aware, I am the first to devise a that occurs, a further turning of the wrench will result in the handle giving way.` That is to say, the jaws 12 and 13 beingV now a fixed part, the handle 14 will swing about the pin 15 against the action of the s ring 19, as indicated in dotted lines'14 in ig. 5. In that event, if sufficient force is applied, it is obvious that the handle 14 will turn about the pin 15 until the shoulder 22 of. the handle abuts against the adjacent end of the jaws. -The workman is thus informed that the fastening member to which the wrench is applied vhas been tightened the pro er amount. Of course, the wrench as mo ified in Figs. 5 and 6 could be turned further, even after the handle has been moved -into the position 14'., because the shoulder 22 of the handle bears against the inner end of the jaws, but it is assumed that4 when this occurs the workman will follow given instructions and not attempt to operate upon the fastening member any further. With the wrench shown in-Figs. 1 to 4, when the fastening member has been tight,- ened the right amount, further turning of the wrench remains futile, because the jaws simply continue to separate. For this reason the first'form of wrench is preferable. But it will be understood that both forms illustrated carry out the underlying idea of my inventicn,namely, .a wrench having yieldable means whereby the tool is automatically rendered inoperative with respect to the member acted upon when the turning j owery applied by the wrench to said mem er exceeds a predetermined amount.

. It is immaterial which of the jaws be regarded as the fixed jaw and which one as the movable jaw. For instance, if the handle portion 1 is rigidly connected to the jaw 6, even leaving the spring 8 as it is, the jaw 3 becomes` the movable jaw. So it is enough to say that the ljaws 3 and 6 are relatlvely movable. c

It will be observed that the jaws of my new wrench automatically resume their normaloperative position under action of the spring afterthey have been rendered temporarily inoperative. This is true of both forms of the invention herein set forth as will be clearly understood. As far as I am wrench possessing this feature.

Although I have herein set forth certain specific'for'ms of my invention, I would have it understood that I do not intend to be limited to the details of rstructure shown and described, for it is obvious that the basic principle of my invention may be carried out in other ways than those herein described by way Of illustration.

What I claim is:

1. A wrench comprising a handle, a pair of relatively slidable jaws carried by said handle for engaging a member tobe turned,

and spring means for normally holding said jaws relatively fixed, said spring means permitting the jaws to separate into an inoperative position with respect to said member when the turning power applied .by the wrench to said member exceeds a predetermined amount, said spring means also causing said jaws to automatically resume their normal operative position after they have been rendered temporarily inoperative.

2.` In a wrench, a handle, a jaw rigidly mounted on said handle, a second jaw movably mounted on said handle, a spring for urging the movable jaw toward the fixed jaw, and means for limiting said movement of the second jaw to provide a normal working opening between the jaws, the tension of said spring being such that the second jaw is movable away from the fixed jaw against tl^e action of said spring when the turning power applied bythe wrench exceeds a predetermined amount.

3. In a wrench, a handle, a jaw lrigidly mounted on said handle, a second jaw movably mounted on said handle, a Spring for urging the movable jaw toward the fixed ,the action of said spring when the turning power applied by the wrench exceeds a predetermined amount, and means for regulating the tension of said spring.

4. In a wrench, a handle, a jaw rigidly mounted on said handle, a second jaw mounted to slide on said handle, an abutment on said handle, a spring coiled on said handle between said abutment and said slidable jaw for urging the latter toward said fixed jaw, and means for limiting the movement of the slidable jaw toward the fixed jaw'to provide a normal working opening between the jaws, said slidable jaw being movable away from said fixed jaw against the action of said spring when thel turning power applied by the wrench exceeds a predetermined amount.

5. In a wrench, a handle, a jaw rigidly mounted 0n said handle, a second jaw mounted to slide on said handle, a nut on said handle., a spring coiled on said handle between said nut and said slidable jaw for urging the latter toward said fixed jaw, said nut being adjustable to regulate the tension of said spring, and means for limiting the movement of the slidable jaw toward the fixed jaw to provide a normal working opening between the jaws, said slidable jaw being movable away from said fixed jaw.

against the action of said spring when the turning power applied by the wrench exceeds a predetermined amount.

FRANK LAMBERT. 

